The invention relates to a telescopic sight with variable magnification, more particularly, to a telescopic sight in which the magnification is changed by means of an adjusting ring.
1. Discussion of Prior Art
Such telescopic sights with variable magnification are already known in the state of the art.
A telescopic sight is known from U.S. Pat. No. 4,072,396 in which the adjusting ring is arranged on the objective lens. However, this position of the adjusting ring is impractical in use. The same holds for the telescopic sight which is known from U.S. Pat. No. 3,423,146.
A telescopic sight is known from U.S. Pat. No. 4,255,013 in which the adjusting ring projects beyond the telescopic sight housing on the eyepiece side. Also, in the telescopic sight which is known from U.S. 3,948,587, the adjusting ring projects beyond its whole circumference out of the housing of the telescopic sight.
In the telescopic sights which are known from U.S. Pat. No. 3,782,822 and U.S. Pat. No. 4,172,634, the adjusting ring is arranged on the eyepiece side, but here also projects from the housing of the telescopic sight over its full circumference.
2. Summary of the Invention
The invention has as its object to obtain a higher stability of the housing together with a simplification of manufacture, with the adjustment taking place at a position which is convenient for use, and the design making possible a substantially smooth surface.
This object is attained according to the invention by a telescopic sight with variable magnification, in which the magnification is varied by means of an adjusting ring and the telescopic sight includes a housing and an eyepiece stub that together form a single part, the adjusting ring is arranged between the eyepiece and the object, and a groove in which the adjusting ring is guided is formed between the telescopic sight housing and the eyepiece stub.
When the telescopic sight housing and the eyepiece stub are made together as a single part, according to the invention, not only is there one part less to manufacture for the telescopic sight, but this simplification of manufacture also has the advantage that the connection between the two parts is solid, and a higher stability of the system is thus obtained.
In an advantageous manner, a groove is formed between the telescopic sight housing and the eyepiece stub, the adjusting ring being guided in the groove. This feature aims at a more secure guiding of the adjusting ring in relation to the direction of the optical axis.
In order to obtain a simple mounting procedure, the adjusting ring is arranged in an advantageous manner around the telescopic sight housing.
The mounting of the adjusting ring is effected in a very uncomplicated manner if the adjusting ring is constructed from two half shell segments, which are connected together in the mounted state to form a circular body. Moreover this permits the materials used for the adjusting ring to be no longer restricted to only certain materials.
In particular, the use of light alloy or a hard plastic for the half shells of the adjusting ring is advantageous.
A pin, projecting from a pin seating which is formed in the adjusting ring, is fitted so that the magnification can be varied; the pin can drive the inner moving elements.
To secure the adjusting ring against inadvertent dismantling into its two component parts, an elastic auxiliary member is to be arranged around the adjusting ring.
The elastic auxiliary member is then advantageously made of rubber, which can in addition seal the opening in the telescopic sight housing.
In order to produce a good connection between the adjusting ring and the auxiliary member, recesses and/or raised portions are to be arranged in the adjusting ring, and engage in corresponding raised portions and/or recesses of the elastic auxiliary member.